On 08/26/2013 10:39 AM, Jerry Leichter wrote:
On Aug 26, 2013, at 1:16 PM, Ray Dillinger <b...@sonic.net> wrote:
Even a tiny one-percent-of-a-penny payment that is negligible between established correspondents or even on most email lists would break a spammer.
This (and variants, like a direct proof-of-work requirement) has been proposed time and again in the past. It's never worked, and it can't work, because the spammers don't use their own identities or infrastructure - they use botnets. They don't care what it costs (in work or dollars or Bitcoins) to send their message, because they aren't going to pay it - the machine they've taken over is going to pay.
Possible, but Doubtful. The bitcoin "wallet" is extraordinarily secure as software goes. Once you've chosen a keyphrase, It NEVER gets saved in decrypted form to the disk, and even in the client software, cannot be decrypted except by explicit command and will not remain in memory for more than a few seconds in decrypted form. Furthermore, the client software does not invoke other programs (like Word or other scriptable attack vectors) under any circumstances. Furthermore any "extensions" like clickable URLs in messages or javascript execution etc or other methods by which external possibly non-secure applications could start up with information from inside the client would be soundly rejected as untrustworthy extensions. People design for and demand an altogether different level of security when you're talking about their own money, and handle the "complexities" of key management with no difficulty. In short, no possibly naive user could convince the developers to do the stupid things that email clients do for coolness or convenience in the context of a financial client. If there were a vulnerability or exploit discovered that allowed a spammer to take control of a bitcoin account, it would be regarded as a MAJOR DISASTER by the community and prompt a fix within minutes, not hours days or months as is the case with "mere" email clients. Consider that *every* *last* *developer* stands to lose at least thousands or tens of thousands of dollars of real, personally owned money if confidence in the network falters. In some cases literally millions. This is not some hypothetical loss to "the company" that they can be ordered to do by some boss even though they think it's a bad idea, nor some hobby that they can allow to fall by the wayside; these people are deeply and very literally invested in the security of the code, and flatly will refuse to do anything that might compromise it. If some company did issue a client with security holes, the usual shrink-wrap "not liable" crap would be completely unacceptable, the lawsuit exposure would be somewhere in the trillions of dollars, and the legal costs to even try to defend a mealymouthed claim of "not liable because of our shrink wrap license" from the resulting firestorm would probably break the company. There are *dozens* of serious, litigous, investors who hold millions of dollars in bitcoin these days, including, among others, the Winkelvoss brothers who spent ten years or more pursuing their infamous Facebook lawsuit. Even if you win that legal fight you're going to lose. The fact that the client is also highly usable is an excellent example of interface design. Bear _______________________________________________ The cryptography mailing list cryptography@metzdowd.com http://www.metzdowd.com/mailman/listinfo/cryptography